Method and machine for pro



5 Sheets-Sheet 1 Wm mm W. H.- BAILEY ori inal Filed larch 1, 1940 IIE'I'HOD AND MACHINE FOR PROFILING HASSES OF HAT BRILL Aprfl 2, 1946.

April 2, 1946.

w. H. BAILEY v IETHOD AND CHINE FOR PROFILING HASSES 0F MATERIAL 5 She ets-Sheei'. 2

Original Filed larch 1, 1940 ai -Wm W. H. BAlLEY April '2, 1946.

METHOD AND MACHINE FOR PROFILING MASSES OF MATERIAL '5 SheetS-Shef. 3

Original Filed March 1,v 1949 April 2, 1946. w. H. BAILEY METHOD AND HAGHIQE FOR PROFILING "A5535 0? MATERIAL Original Filed March 1, 1940 E'Sheets-Sheet 4 April 2, 1946. w. H. BAILEY v 22,737

METHOD MACHINE FOR PROFI LING MASSES OF MATERIAL Original Filed March 1, 1940:

5 Sheets-Sheet 5 NNL Reissued Apr. 2, 1946 UNITED STATES PATENT OFFICE 22,737 METHOD AND MACHINE -FOR PROFILING MASSES F MATERIAL William H. Bailey, Pueblo, 0010., assigiicr'to The Colorado Fuel & Iron "Corporation, Denver, 0010., a-corporation of Colorado Original No. 2,317,244, Apr-i120, 1 943,FSerial No. 321,798, March 1, 1940. Application for iei's'sue April-18, 1944, Serial No. 531,621

45 Claims.

This invention relates to the production of desirableprofiles upon :a suitable -mass of. material byrolling suchmass between one or more pairs oirelatively movable dies. 'The invention will be particularly described in connection with the rolling of threads-in bolt blanks, screw blanks and the like, but it is to be understood that in its broader aspects the invention is not limited to thread forming and that blanks for such purposes are only exemplary of masses which may have their profiles changed by rolling between relatively movable dies in accordance with my invention.

"The present methods-and machines for rolling masses between relatively movable dies are limited to the forming of screw threads on bolt blanks, screw blanks and the like. Such machines as heretofore have been proposed have been equipped with dies having thread-forming ridges and .grooves. All other profiling has been done by some means other than rolling between relatively movable dies, as, for example, by forging, upsetting, heading or machining.

At the present time it is more or less standard practice to thread certain types of bolt blanks by causing the blank to be rolled under pressure between a pair of dies having thread-forming ridges and grooves of a shape to impart the desired thread term to the blank. One method now in extensive use for forming screw threads into blanks is to roll the blank between a single pair of relatively movable reciprocating platen dies having thread-forming ridges and grooves of a shape to impart the desired thread form to the blank. The part of the blank to be threaded is vformed with a diameter slightly smaller than the diameter of the desired thread and, roughly, about equal to the pitch diameter of the thread to be formed. The reciprocating die on its forward stroke engages a bolt blank and causes it to roll along between the stationary and reciprocating dies until the end of the stationary die is reached, when the bolt with the thread formed thereon is ejected from the machine. The dies are set so that during the rolling of the blank vit is subjected to a pressuresufiicient to cause the thread forming ridges of the dies to sink or be embedded about half way into the blank, and 'the metal thus displaced to be forced to fill the grooves between the thread forming ridges. 'Suh machines are automatic in operation and have means working in synchronism with the reciprocating die for feeding abolt blank to be engaged and rolled between the threading dies on each forward movement of the reciproeating die, so that a blank is threaded and ejected from the machine on each reciprocation of that die. I i

Machines of the general type described above, while being simple in operation and producing threaded bolts at relatively low cost are not entirely satisfactory, and it' is "well known that the threaded portion of the bolts produced by them are nei ther truly cylindrical, nor truly circular in cross-section, with the result that nuts .placed on :such bolts do not uniformly fit the bolt threads. The dies exert a very substantial pressure at oppositesides of the blank, and as the thread-forming ridges are depressed into the blank the mat'erial'is not onlydisplac'ed so as to fill the grooves, but the pressure on the blanks results in a certain amount'of 'longitudinal flow of the metal "away-from "the 'central portion of the part being threaded, which longitudinal flow is greatest *at'the'ends of thethreaded iportion because the least resistance to such flow -is at the ends. That results in -a-finished bolt with threads of a smaller dia'me'ter =at the ends than at the central .portion.

As the threading dies of "the present bolt threading machines engage only the opposite sides of the bolt blank and as the displacement of metal during the threading operation causes the portion of the blank being threaded to be subjected to very high pressures there is also 'a tendency, especially if the diameter of th'eblank is too large, for the metal of the blank to 'fiow outwardly in the direction of the surface not engaged by the dies and the portion of the bolt being threaded to become out-'of"-round by reasonof the pressure applied by the -dies'oi1=the two sides of the bolt contacted at any specificinstant.

The stresses set up in the bolt blank during the threading thereof, *as described above, are so great that under certain =ci'r'cumstances the central portion of the blank becomes fractured, which, if severe enough, will mechanically l'produce a cavity or pipe and greatly weaken the bolt.

The matter of bolt and nut fit is becoming a subject of grave concern to the railroads and other users of bo1ts,.-as bolt failures are not infrequently due to imperfect or non-uniform fit of the nut.

By the present invention the disadvantages of the present methods and machines for rolling threads into bolt blanks and the like are overcome and a method and machine are provided which will :produce screw threads which are uniform in pitch diameter, major and minor diameters, andth-read-profile, in the entire length of the threaded portion, so that bolt failures due to imperfect or non-uniform fit of the nut will be eliminated, or reduced to a minimum.

The present invention is adapted for either hot or cold rolling, and 'whi-le it is primarily concerned with the threading of track bolts, such as are used in securing railroad rails and fish plates together, by means of cooperating stationary and reciprocating platen dies, it is applicable to the threading of boltsfor other purposes. Also, the broad aspects of the invention 2 are applicable to other types of thread-rolling machines. p

Whereas the method of rolling threads into bolt blanks now in common use involves but a single operation on the cylindrical portion of theblank to be threaded, the present invention contemplates two operations on that portion of the bolt blank, in that before being acted upon by the threading dies the portion of the blank to be threaded is acted upon by one or more relatively movable initial or forming dies which correct the blank with reference to diameter and roundness and also preform the portion to be threaded, preferably by reducing the diameter of, and imparting a generally concave contour to that portion of .the bolt blank. The blank with its concave contour and trued to proper size with regard to diameter is then subjected to the threading operation by rolling under pressure between one or more pairs of relatively movable dies. By reason of the fact that more metal is disposed at the end portions than at the central portions of the part of the blank to be threaded when it enters the threading or finishing dies, longitudinal flow or elongation, which is greatest at the end portions, .is compensated for. Also by reason of the fact that the blank is trued to an exact diameter and concentricity no overfilled, underfilled or eccentric threads are produced. Thus the present invention, which comprises rolling the blank between pairs of relatively moving dies which preform and true the blank in addition to threading it, as distinguished from the present practice which is limited to threading the blank, fulfills the requirements necessary to produce an accurate screw thread, that is, disposition of metal in a manner to effect compensation for longitudinal flow or elongation at the ends, and truing for'diameter and con centricity.

The present invention further provides for so preforming. the blanks as they pass between the initial or forming dies that the body portion of the bolts and the like .which are not threaded may be of the same diameter as the major diameter of the threaded portion; or such portion may be of greater, or of less diameter, as desired, than the major diameter of the threaded portion. That may be accomplished with the forming dies either by reducing a bolt blank having a diameter equal to the desired shank diametenon its portion to be threaded, to the diameter required for rolling a full thread, or by reducing a bolt blank, having a diameter equal to the diameter required for rolling a full thread, on its shank portion to the desired diameter. Those operations can, of course, be made simultaneously with or before the truing up and the .proper shaping of the part of the bolt blank to be threaded, or a blank can be reduced on the shank portion and on the portion to be threaded to the required size.

The extent of concavity imparted to the bolt blank is such that during the threading operation the blank is subjected to sufiicient' pressure to thoroughly consolidate the metal in the threads and to bring the central threads out into accurate longitudinal alignment with the end threads, without, however, causing the blank to be subjected to a pressure such as will cause the central threads to have a larger external diameter than the end threads, or such as will subject the central portion of the bolt to stresses such as will cause fracturing thereof.

The subjecting of the bolt blanks to the initial or forming dies to impart the concave shape thereto may be done before they are fed to the thread-forming machine, but preferably is done by the stationary and reciprocating threading dies, and also preferably by arranging the forming and threading dies in tandem. When the forming and threading dies are so arranged the bolt blanks may be fed to the forming dies in the same manner as they are now fed to the threading dies, and on each forward movement of the reciprocating die a blank will be trued and concaved by the forming dies and delivered to a position to be engaged and threaded by the threading dies. on the next forward movement of the reciprocating dies, so that on each reciprocation of the reciprocating dies, after the first one, one bolt blank will be trued and concaved while the preceding blank will be threaded and ejected from the machine. Thus, while the present invention requires the performing of an additional operation on the bolt blank a bolt blank is threaded and ejected on each reciprocation of the reciprocating threading die, as in the present machines.

The invention will be further described in connection with the accompanying drawings in which a bolt threading machine of the reciprocating platen type is illustrated as an example of a machine for forming a desired profile ona mass of material. However, it is to be understood that such further illustration and further description is by way of exemplification and that the invention is not limited thereto, except to the extent set forth in the appended claims. In the drawings:

Fig. 1 1s a plan view of a bolt threading machine embodying the present invention.

Fig. 2 is a side elevational view.

Fig. 3 is a transverse sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is a transverse sectional view on line 4-4 of Fig. 1.

Fig. 5 is a transverse sectional view on line 5-5 of Fig. 1.

Fig. 6 is an enlarged plan view of that portion Fig. 1.

Fig. 7 is a longitudinal sectional view on lin 1-1 of Fig. 6.

Fig. 8 is a diagrammatic view illustrating the position of the dies and a pair of bolt blanks at the beginning of a stroke.

Fig. 9 is a diagrammatic view illustrating the position of the dies and a pair of bolt blanks an the end of a stroke.

, Figure 10 is an enlarged transverse sectional view on line l0lll of Fig.6.

- Fig. 11 is an enlarged transverse sectional view on line l|--II of Fig. 6. i Fig. 12 isa perspective view of the flapperactuating member. 7

Referring to the drawings, the frame of the machine comprises a forward section I, a rear. section 2 and an angular extension 3 forming a The shaft 6 carries flywheels. 9 and a pair of small spur gears l0 and II meshing respectively with large spur gears I2 and [3 carried by the inner ends of a pair of aligned stub shafts l4 and I5 supported in bearings l6 and I], also on The motor section 2 of 'the frame.

The large .gears 12 and 13 .areconnected adjacent their outer edges by a-cr-ank pin It 'to which-the rearendof a' connecting rod 1 9 isconnected.

The-forward end of :the connecting rod 49 is .rightextension 22, respectively. A cap plate .25

is sec ured over theupper edge vof the upright extension 22, wear plate 24 and the .upper edge of the die block 2|, to complete the guideway for the reciprocating die block 2| and to hold it in properposition during reciprocation.

Die block 2| is provided with dovetailed recesses 26 and 21 for receiving-a pair of dies 28 and 29 arranged in tandem and removablyheld within the recesses .by clamps or hold-downs 36 bearing upon the upper edges and the outer end faces of the dies. Liners 3| and .32-are-interposed between the rear ends vof the dies 28 and '29 and the rear ends-of recesses26'and 21, and wear plates 33 and Y34 are secured to the inner side of the die block behind theliners 3| and 32 respectively.

The reciprocating dies .28 and 29 cooperate with a pair of stationary-dies -35 and.36, also arranged in tandemand adjustably secured to the inner side of an upright portion.22'-of the frame section I by stopscrews 31. The dies and 36 are held in their adjusted position by clamps or hold-downs 38 bearing .upon their upper edgesand their outer ends.

The reciprocating die 28 and the stationary die 35 with which it cooperates are initial forming or shaping dies shaped so that as a bolt blank passes between them in the manner hereinafter described the portion thereof to bethreaded will be concaved or otherwise shaped. The reciprocating die 29 and the stationary die .36 with which it cooperates are threading dies and are provided with the usual inclined threading ridge to impart a'thread to the previously shaped bolt blank when it is rolled 'be tweenthose dies.

For operating the mechanism 'for feedingbolt blanks to the formingdies, the outer end of the stub shaft H! has a .cam 39 rigidly secured thereto and rotating against a roller 46 mounted in the lower end of a downwardly-extending rocker arm 41 rigidly secured to the outer end of a rocker shaft 42. The inner end of the rocker shaft 42 has an upwardly-extending rocker arm 43 to which is connected a link 44 slidable through a guide bracket or the like 44 secured on the frame section I. The for-ward end of the link 44 is connectedto the lower end of a rocker arm 45 rigidly secured to a rocker shaft 46 mounted in a bracket "41 secured to the frame section'l. The upper end of the rocker arm 45 is connected through links 48 to a series of slides 49 which control the feeding of bolt blanks from a feed chute to'the point a in Figs. 6 and 8 where they rest upon aforwardly-projecting to'e piece 50 of a starter 5|, and in position to be pushed between the initial forming dies 28 and 35 as the former begins .its forward movement.

The feed chute for the bolt blanks .to be threaded and the details of the mechanism for feeding the ,bolt blanks to the position ais not shown, as such mechanisms are welliknown and .formndpart .cf theg'presentdnvention. It; is sufficient .to ;point out "that the :operation .of the slides 49 in the manner above :described -.is synchronized' with therre'ciprocation-of the .die block 21 *anddies 2B and--23-carried :thereby :so that one to form a sloping shoulder 53' for temporarily retaining apreviousiy concaved bolt blank .in 'the position. b, :.ready .to .be pushed between .the

threading dies .29 sandr 36 as the former begins its forward -movement.

.Inorder to operate the-.startersforpushing'the boltwblanksbetween the :formingdies and 135 and .the threadingdies 29 .and .236, a cam :54 is rigidlysecured to thetstub shaft .I5 between the large gear L3 and the shaft bearing 11 :and rotatesagainst a clevis.block55 secured to thezrear end of a starter actuating rod56having bearing blocks .56 rigidly. secured .thereto and slidable in bearings :57 and Z5.8:in. the .frame .sections 2 .and l respectively. v.Actuating trod -56 has a boss 59 formed on. thelowerside thereof intermediate its ends for.slidably-receivinga .rod 60, the -.forward end .of which-ispltovided with vavnut 62 forming a bearing for the forward end of :a compression spring .63, the .other .end .of .which .bears against the forward faceof the boss 59 .on the rod 56. The :rear end of .the .rod 60 which extends through the .bracket 6| has ,a .nut .64 threaded thereon so that the .forceexerted bycthe spring '63 against the '.boss..59 may be adjusted. The spring .63 bearingagainst the boss 59 on rod .56 yieldingly maintains .the .olevis block secured I to the .end .of .the :rod 56 .in .contact with the periphery of the cam 5.4,..andtends to restore the rod '56 .to its .rearmost positionafter the high pointon the .camhas passed theclevis block .55.

65 through whicha pair of .rods 66 and 61. are,

slidable. The forward .end of the rod 66 is threaded into the .rear .end (of the starter 5|. The forward end of the .rod6'l is threaded into the rear .end of asimilar .starter '69 located .in ,a horizontal planebelowthe starter l5l and having a toe piece "for receivingthe .end ofa bolt in positionb, Figs. 6 and .8. v.Asshown .in Fig.4 the starters 5| .andfl69 areslidable .inbearing blocks H and 12 mounted within an upright extension 73 secured to frame section .I.

Nuts 14 and Hare-threaded onto the rods 66 andlli'lbetween the.angular=extension*65 and the rear "face of the [starters 5| and 69 and form bearing surfaces "for the forward ends of compression .springs 16 and 11 respectively. The rear ends of the compression springs bearagainst the forward face of thetangular extension 65. Nuts 18 and 19 are threaded onto the rear ends of the rods 66.and'61 which extend throughithe angular extension 65. .Lockrnuts and 8| are threaded onto the forward ends vof the rods 66 and -61 and bear against the rear face of the starters 5| and 69. .Bylsuitably adjusting the nuts 14 and 1,5 and thexnuts 'lflfa'n'd t9 the proper position of the toe pieces 5B-and '16 :of the'starters 5| an .69, respectively, the tension :of the springs 16 and 1.1, may be adjusted. The springs 16 and I1 form resilient actuating means for the starters 5I and 69.

As best shown in Figs. 6 and 7, a bolt blank receiving hopper 82 is positioned to receive the bolt blanks at the end of the first pass after they have been rolled between the initial forming dies 28 and 35. The hopper is generally U-shaped in horizontal cross-section and comprises downwardly and inclined side walls 83 and 84 and a downwardly and inwardly slopingend gate 85 normally held by a leaf spring 96 in a position to close the space between the forward ends of the side walls 83 and 85. The rear side of the hopper is open to receive bolt blanks at the end of the first pass.

The outer end of the stub shaft I5 has a cam 81 rigidly secured thereto and rotating against a roller 88, mounted in the upper end of a rocker arm 89 rigidly secured to the outer end of a rocker shaft 90. A rocker arm 9| is rigidly secured to the inner end of the rocker shaft 90 and has its lower end connected to a connecting rod 92, the length of which may be adjusted by a turn buckle or the like 93. The forward end of the connecting rod 92 passes through one of a series of reinforcing webs 94 of the frame section I and has a clevis 95, adjustably secured thereto and connected to the free end of a rocker arm 96 rigidly secured to the lower end of a vertical shaft 91 extending upwardly through the frame section I to a point above the top surface thereof. A flapper-actuating member 98 is rigid- 1y secured to the upper end of the rocker shaft 91 and has a cylindrical outer end portion 99 received within a slot I formed in a flapperllll slidable along the upper surface of the frame section I and having longitudinally extending slots I02 and I03 within which are positioned blocks I04 and I05 rigidly secured to the top surface of the frame section I by bolts I08 and I0! respectively. The blocks I04 and I05 guide the flapper IOI during its actuation by the actuating member 98. The flapper bar IOI has on its inner end a projection IOI extending down to the bottom of the hopper 82. When the fiapper'bar is actuated, this projection opens and closes the rear side of the hopper 82.

A nut I88 is adjustably secured to the connecting rod 92 between the reinforcing web 94 and the clevis 95 and forms a bearing for the outer end of a compression spring I09, the inner end of which bears against the reinforcing web 94 of the frame. The compression spring I09 exerts a force normally tending to move the connecting rod 92 to the left in Fig. 2, thereby to maintain the roller 88 constantly in engagement with the periphery of the cam 81.

As the machine operates, the rotation of cam 81 causes the flapper bar IOI to be reciprocated back and forth and the actuating mechanism isso constructed-that the movement of the flapper bar is synchronized with the reciprocation of the forming the 28 and moves to its inner position to close the rear of the hopper 82 Just after a bolt blank has been ejected from between the forming dies 28 and 35 into the hopper 82.

In the operation of the machine a bolt blank to be threaded is fed from the feed chute to position a, Figs. 6 and 8, where it is received by the toe piece 50 of the starter member 5I.- As the die block 2| carrying the dies 28 and 29 moves forward, the starter member 5| is pushed forward and forces the bolt blank along the inclined shoulder 53 of the stationary die 35'into a position where the opposite sides thereof are engaged by the forming dies 28 and 35. The forward movement of the reciprocating die 28 causes the bolt to be rolled under pressure between it and the stationary die 35 until it reaches the forward end of the latter. The bolt blank with the por- .tion to be threaded, concaved as shown in Fig, 10,

is then ejected from between the forming dies 28 and 35 and passes into hopper 82 through which it drops to the lower level of the cooperating threading dies 29 and 36. The bolt is then in position b, shown in Fig. 8. As soon as the concaved bolt blank passes into the hopper the flapper bar IN is moved to its innermost position to close the rear side of the hopper 82, as shown in Fig. 6. On the next forward movement of the die block 2|, the bolt blank, with the portion thereof to be threaded concaved, is forced by the pusher member I59 along the sloping shoulder 53' of the stationary die 36 to bring the bolt blank into a position to be engaged onr opposite sides by the cooperating threading dies 29 and 36. The forward movement of the die 29 causes the threads to be rolled into the bolt blank in a well-known manner. At the end of the forward movement of the die 29 the bolt properly threaded is ejected from the machine.

From the foregoing description it will be seen that during the first pass the portion of the bolt blank which is acted upon by the initial forming dies 28 and 35, that is, the portion of the blank which is subsequently to be threaded, is given a concaved contour. During the second pass the thread is rolled into the bolt blank in the usual manner. However, as the portion of the bolt blank to be threaded has been given a concave shape the larger diameter at the ends compensate for the flow of metal in the longitudinal direction of the blank away from the central portion to be threaded, and a bolt with a thread of uniform diameter results. The extent of the concavity imparted to the bolt blank during the first pass is such that during the threading operation, which takes place during the second pass, the blank is subjected to a sufficient pressure to thoroughly consolidate the metal in the threads and to bring the central threads out into accurate longitudinal alignment with the end threads, without having caused the portion of the blank being threaded to be subjected to a pressure which will cause the bolt being threaded to be forced out of round, or the central threads to have a larger external diameter than the end threads, as is common with bolts having threads rolled therein by a single operation and without any initial concaving of that portion of the blank which is to be threaded.

The initial forming dies 28 and 35 may have smooth faces or faces provided with ridges and grooves to partially form the desired thread before the blanks are passed to the dies 29 and 35. In the latter case the initial forming dies 28 and 35 will perform the dual function of preforming the bolt blank so that the portion thereof to be-threaded has a generally concave contour and of imparting a partially formed thread to be completed by the finishing dies 20 and 36.

While the present method of rolling threads into bolt blanks necessitates an additional operation upon that portion of the bolt blank which is to be threaded, that is not a disadvantage, because on each reciprocation of the movable dies one bolt blank has the portion to be threaded given a concave contour while the preceding bolt blank is being thread'ed. Thus the-present machine causes abolt blank to be threadedfor each reciprocatiorrof' the movable dies, as-inpresent machines.

A machine embodyingthepresent invention has been described with respect:to preliminarily giving the" blanks a general concave form prior to rolling'itto develop a thread thereon. However, it is understood-'thatthe' invention also contemplatesmachinesin which the blanks are prelimi narily rolled merely to bring them to proper cylindrical shape and size preparatory to therolling of.a thread in them.

I claim:

1. The methodof imparting a non-linear profile longitudinally ofa generall cylindrical mass of material which comprises. forming anintermediate portion of that part. of' the masspf material which is tobelprofiledvso that the area of. a. cross-section. normalto, the length of I the mass of materialat saidintermediate portionis lessthan the area ,ofja like cross-section at the end-portions. of saidpartofjithe massof material, and pressingthe. desired non-linear profile into that partof themass of-material Whichis to be profiled. while said intermediate porticnhas a less cross-sectional areathan said endportions,

the shape of theprofiling member, its. relation.

during. the pressing. operation. to the mass of material and the. pressure. under.v which the pressing of the profile intothe mass ofimaterial takes place being such. that. material insaid intermediate and end portions of the. part ofthe mass of material beingprofiled is brought intolongitudinal alignment.

2. The. method of. imparting a non-linear pro.- file longitudinally of agenerally. cylindrical mass of material. which. comprises forming. an intermediate portion. of that. part of the mass of material which is to beprofiled so that thereis aless volume .of. material there than at the end portions of .saidpartofithe mass: of material, and

rolling the-desirednon-linear profile into that part of the mass of material which is to be-pro- ,filed, while there.isaa'less'volume. of material-.at said intermediate portion than there is at said end portions, between platen dieszto impart the desired profile thereto; the pressure: under which the mass of materialis rolled: being" such that material in said: intermediate portion: is. forced outwardly sufiiciently to bring its: profiledsurface into alignmentiwithzthe' profiled'surface at the end portionszof saidpart of: the mass of material;-

3; The methodxof impartinga non-linear profile longitudinally of agenerally cylindrical'mass of material which comprisesformingan intermediate portion. of that part ofthemass of sufficiently to bring its-profiled surfacejnto alignment-withthe profiled: surface at" the end portionsofsaid partof themass ofmateriali 4: The" method of preventing the formation of working a uniform diameter blank-which comprises forming the majorportion of 'the-part ofthe blankwhich is to be profiled, including the central'portion thereof, with agenerally-concaved contour, and pressing the desired profile into that part of the blankwhichis to be profiled, the shape of the profile-forming member, its relation during the pressing operation to the blank and the pressure under which the pressing of the profile into the blank takesplace being such that material in said central portion isforced outwardly sufficiently to bring its profiled surface into alignment with the profiled surface at the end portions of said part of the-blank.

5. The-method of profiling a generallycyllndrical blank'which comprises impartinga concaved contour to the major-part of. that; portion of .the blank'which iSItO be. profiled, and rolling;

the desiredprofile intosaidportion of 'theblank, the shape of the profile-forming member, itsrelation during the rolling operation to the blank,

and the pressure under which the rolling of'the profile into the blank takes; place beingsuch that material ingsaid concavedgportion is forced outwardly sufficiently to bring. its profiled. surface into longitudinal alignment."

6. The method of profiling a, generally cylindrical blank which comprises preforming the entire part of the blank whichis' to be profiled so that it is of generally concave contour, andv thread to a bolt. blank which comprises forming an intermediate portion of thatpart. of the bolt blank which is to be threaded so that thereis a less volume than atthe endportionsof said part of the, bolt blank, and, pressing. a thread .into. that. part of the bolt blank which is to be.

threaded, the shape of the thread-l-formingmeme ber, its relation during the pressing operation to, the boltblank and the pressure under. which the pressing of the thread intothe bolt blank takes place being such that the threads formed insaid intermediate andend portions, of,the part of1the blank, being threaded are brought nal alignment.

8. The method of thread to a bolt blank'which comprises forming an intermediate portion, of that part of the bolt blank which is to be threadedso that there is a less volume of material there than at' theend portions of said part of the bolt blank,-and pressinga thread into that. part of" the ,bolt" blank into longitudiwhich, is .to be threaded, the-shape of the threadforming member, its relation during the pressing operation to the bolt' blank and the pressure under which the pressing of vthe threadinto the:

bolt blank, takes place being such that; material. in said intermediate portion is forced outwardly sufiiciently to bring; the threads formed in said intermediate, portion. into longitudinal I alignment Withthe end threads! 9. The; method of: imparting a cylindrical thread to a bolt blank which comprises forming a non-uniform-diameter profile a as theresult of" imparting a cylindrical an intermediate portion of that part or the bolt blank which is to be threaded so that there is a less volume of material there than at the outer or free end portion of said part of the bolt blank, and rolling a thread into. that part of the bolt blank which is to be threaded, the shape of the thread-forming member, its relation during the rolling operation to the bolt blank and the pressure under which the rolling of the thread into the bolt blank takes place being such that material in said intermediate portion is forced outwardly' sufliciently to bring the threads formed in said intermediate portion into longitudinal alignment with the threads formed at the outer or free end portion of said part of the bolt blank.

10. The method of imparting a cylindrical thread to a bolt blank which comprises forming an intermediate portion of that part of the bolt blank which is to be threaded with a smaller diameter than the end portions of said part, and rolling a thread into that part of the bolt blank which is to be threaded, the shape or the threadforming member, its relation during the rolling operation to the bolt blank and the pressure under which the rolling of the thread into the bolt blank takes place being such that material in said intermediate portion is forced outwardly sumciently to bring the threads formed in said intermediate portion into longitudinal alignment with the end threads.

11. The method of imparting a cylindrical thread to a bolt blank which comprises preforming the entire part of the bolt blank to be threaded so that the intermediate portion of that part 01' the bolt blank is of a smaller diameter than the end portions of said part of the bolt blank, and rolling a thread into that part of the bolt blank which is to be threaded, the shape of the thread-forming member, its relation during the rolling operation to the bolt blank-and the pressure under which the rolling of the thread into the bolt blank takes place being such that material in said intermediate portion is forced outwardly sumciently to bring the threads formed in said intermediate portion into longitudinal alignment with the end threads.

12. The method of imparting a cylindrical thread to a bolt blank which comprises forming the central portion of that part of the bolt blank which is to be threaded with a smaller diameter than the end portions of the part of the bolt' blank to be threaded, and pressing a thread into that part of the bolt blank which is to be threaded, the shape of the thread-forming member, its relation during the pressing operation to the bolt blank and the pressure under which the pressing of the thread into the bolt blank takes place being such that material in said central portion is forced outwardly sufliciently to bring the threads formed in said central portion into longitudinal alignment with the end threads.

13. The method of imparting a cylindrical thread to a bolt blank which comprises forming the central portion of that part of the bolt blank which is to bethreaded with a smaller diameter than the outer or free end portion. of the part of the bolt blank to be threaded, and rolling a thread into that part of the bolt blank which is to be threaded, the shape of the thread-forming member, its relation during the rolling operation to the bolt blank and the pressure under which the rolling of the thread into the bolt blank takes place being such that material in said central portion is forced outwardly suificiently to bring the threads formed in said central portion into longitudinal alignment with th threads at the outer or free end portion of said part of the bolt blank.

14. The method of imparting a cylindrical thread to a bolt blank which comprises imparting a generally concaved contour to that portion of the bolt blank which is to be threaded, and rolling a thread into said portion of the bolt blank, the shape of the thread-forming member, its relation during the rolling operation to the bolt blank and the pressure under which the rolling of the thread into the bolt blank takes place being such that material in said concaved portion is forced outwardly sumciently to bring the threads formed therein into longitudinal alignment.

15. The method of imparting a cylindrical thread to a bolt blank which comprising forming the central portion of that part of the bolt blank which is to be threaded with a smaller diameter than the end portions, and rollin the portion of the bolt blank to be threaded between thread-forming dies which engage opposite sides of the bolt blank, the shape of the thread-forming dies, their relation during the rolling operation to the bolt blank and the pressure under which the rolling of the thread into the bolt blank takes place being such that material in said central portion is forced outwardly sufllciently to bring the threads formed in said central portion into longitudinal alignment with the end threads.

16. The method of imparting a cylindrical thread to a bolt blank which comprises simultaneously forming an intermediate portion of that part of the bolt blank which is to be threaded with a smaller diameter than the end portions and with a partially formed thread, and thereafter rolling the portion of the bolt blank to be threaded under pressure between finishing dies which complete the formation of the thread on that part of the bolt blank to be threaded, the shape of the finishing dies, their relation during the rolling operation to the bolt blank and the pressure, under which the formation of the threads is completed being such that as the formation of the threads in said intermediate portion is beingcompleted the material in said intermediate portion is forced outwardly sufficiently to bring them into longitudinal alignment with the end threads.

17. The improvement in the method of threading a bolt blank in which the part'oi' the bolt blank to be threaded is engaged on opposite sides by grooved thread-formlng dies and the bolt blank is rolled between said dies to form the thread thereon, which comprises first engaging the end portions of the part of the blank to be threaded with the thread-forming dies so that longitudinal flow of the material due to the threading operation is away from the middle of the portion being threaded and the grooves of those portions of the threading dies which lie opposite the central part of the portion of the blank being threaded ar progressively filled.

18. The improvement in the method of threading a bolt blank in which the part of the bolt blank to be threaded is engaged on opposite sides by grooved thread-forming dies and the bolt blank is rolled between said dies to form the thread thereon, which comprises forming an intermediate portion of that part of the bolt blank which is to be threaded with a smaller diameter than the endportions, of: said part; and

first; engaging; the end portions: of; said: part ofi the; bolt blank: with; the thread-f ormingrdies; so: that longitndinali now of: material due to; the; threading; operation isaway from themiddleof; the portion being threaded and the grooves-:. of" those; portions of the threading dies which lie. opposite; the central part of the portion of: the blank'being threaded are progressively. filled;

19 A; machine for profiling a maSsof mate-- rialwhich comprises means for preforming anintermediateportion of that part of the mass; of; material to be profiled so that there: is. less volumeoof material there than at the'en-d portions of said part, a finishing die having a.

planar thread-forming face, means for; feeding;

theapreformedmass of material-to said finishing diet. and meansfor pressing said finishing: die: against the massof material with. the planar: thread-forming; face thereof bridging saidiinters mediat portion; of less volume. and with; a force: sufllcienhto; cause material in; said intermediate pQl-tlon to. be forced outwardly sufficiently to bring; said intermediate portion into longitudie. nal alignment'with the end portions of said part oi-theemass. of material;

20. A. machine for profiling a mass of mate rialuwhichcomprises means for preforming the Part of themass, of material to be profiled,

that anintermediate portion, of the part, there- 01. to. beprofiled is of smaller diameter than:v the: end-portions of said part, a finishing die having; a, planar thread-forming face, means for feed.- lng the. preformed mass, of material tosaid; finishing die; and "means for pressing said finishmg; die: against said mass of material with the planar. face thereof bridging said intermediate portion of smaller diameter and with a forcesuflicientltolcause material in said intermediate portion; to: be, forced outwardly sufficiently to bring said intermediate; portion into longitudle naL alignment withthe end portions of said. part: oaths-mass QimateriaL 2i. Armachine-ior profiling a mass or mate rlaLwhichcomprises a pair of relatively movable finishing-dies; adapted to engage, a blank; and to: roll: al desired profile thereon, a pairof; relatiyely, movable preformindies positioned to the rear of said finishing dies, for rolling bla Y- SJbetweenr them. and, imparting to an. intermediate portion: of, said blanks a smaller diameter: than the, end portions: of i said parts of the blanks; and means 101 feeding. preformed blanks, from said mteformin dies-to saidfinishing dies.

22:.A-lmachine for, formingcylindrical threadsonuatbolt blank which comprises meansion pro forming an intermediate portion of that. partof: the-blank which is tobe threadedrso thatthere law a less volumeof material there? than at the;

end portions: of said part, a'threadingdiehaving; l

a. planar thread-forming face,- means for: feed? ing; the: preformed bolt blank: to saidflnishing, die, and means for pressing said finishing die against the; part, of; the blank: to be, threaded with-lthe -.p1anar; face thereof: in: parallelism; with 'thaaxis of. the. blank and with a; forces uflicient to form. threads therein, and to cause; immaterial;

in. said? intermediate portion, to: be; forced; out: wardlrsnificientiy to bring the;- threads formed at? said: intermediate portion into; longitudinal? alignment: with-the end threads.

Al'machinefor threadingzbolt blanks-:lwhich: comprises: a. pair: of relativelymovable: thr.ead forming: dies; adapted; to N engage a. boitsi blank to form: ai flnishedjthmad thereon; a; pair; Ofi role,

threadzona the: bolt blank is completed as said finishing; dies;- movenrelative tov on another.

24'... A: machineriior; forming cylindrical threads oniaboltzblankmhich comprisesmeans for preforming; an, intermediate; portion-- of the part of I thepbolti blankzbethreadedzwith a smaller diameter than: the; end; p rtions of said; part;v areciprocating; die: having; a substantially planar" tbreadrimfmin afacet means for: bringing the preformed blank into engagement with. said thread-forming: di e witlr the axis; or the: blank paralleh to the; planar: thread-forming; face; of: said; reciprocating. die; andi; means for pressingthe; die against the portion of: the. preformed: blanks tobe; threadedjwith the planar thread;-

forming face; thereof; bridging: said 1 intermediate formed at, said intermediate.- P01110111 into 1ongi.--

tudinal alignment-withthe end threads.

25.; A1 machine-forforming cylindrical threads one a1 bolt: blankt which: comprises a stationary die. having; a-Mplanar: thread-forming; face, a re.- ciproeating; die; for cooperation. with said; stationary die: having. a: planar thread-formingface parallel withthe planar: thread-forming face of the stationary: die-, said,- (831 being. adapted to engage opposite sides. of, a. bolt blank and to cause-,threadgtozberolled, intoit; means for ime partingi-a generallyrconcavedi contour to, that: portion of the bolt blanks: which: are? to: be threaded; and means: for feeding such; preformed; blanks said stationary and: reciprocating dies: with the concaved portions opposite said di'esz 26: A machine-for: profiling a blank which comprises: a pair oI preform-ing dies: for engag ing opposite sides of blanks and reducing thediameter of the: central portionof those parts of t-heblanlts which are-tobe profiled; a pair of finishingdies; means for feeding blanks to said preformingdies; means for feeding preformed blanks from said preforming dies to said finishing dies; and means for causing-said finishing dies to engagezoppositesidesrof,the blanks to roll the desired profile into them: and to cause the central portion of reduced diameter to be forced routwardly into longitudinal alignment with the adjacent;profilediportions.

211A. machine for. imparting a cylindrical thread tobolt;blankswhichlcomprisesa pair of forming dies for engaging opposite, sides or, bolt.

blankslandreducing thediameter. or. the central portion, of, those: parts: of, the. .blanks, which, are to be threadeda. pair; of, threading dies, means for, feeding; bolt; blanks. tosaidforming dies, means: for, feeding the bolt blanks; fronr said .t'orming. (11351-1391 said. threading; dies, and means for; causinggssaid threading, di8S-7tO engage oppositev sides; of? the blanks to roll a; desired thread into; themi and-2 to: cause material; in 'said centifal. portion of: reduced diameter-to; be; forcedioutiwardiyi suficlentiw tori brintei the threadsv formed in said central portions into longitudinal alignment with the end threads.

28. A machine for imparting a cylindrical thread to bolt blanks which comprises a pair of forming dies for engaging opposite sides of bolt blanks and reducing the diameter of-the central portion of those part of the blanks which are to be threaded, a pair of threading dies, means for feeding bolt blanks to said forming dies, means for feeding the bolt blanks from said forming dies to said threading dies, and means for causing said threading dies to engage opposite sides of the blanks to roll a desired thread into them, and to'cause material in said central portion of reduced diameter to be forced outwardly sufllciently to bring the threads formed in said central portions into longitudinal alignment with the end threads, said threadlng'and forming dies being arranged in tandem.

29. A machine for threading bolt blanks which comprises a pair of forming dies for engaging opposite sides of bolt blanks and imparting a generally concave contour to the portion thereof which are to be threaded, one of said forming dies being stationary, means for reciprocating the other of said forming dies, air of thread-forming dies having planar thread-forming faces, one of said threading dies being stationary, means for reciprocating the other of said threading dies, means for feeding bolt blanks to said forming dies, means for feeding the bolt blanks from said forming dies to said threading dies, and means for causing the planar thread-forming faces of the finishing dies to engage opposite sides of the concaved portions of the blanks, while in ubstantial parallelism with the axes of the blanks, to roll the desired thread in the concaved portions thereof under' a pressure sufficient to cause material in said concaved portions to be forced outwardly sufllciently to bring the threads being formed in said portions into longitudinal alignment.

30. A machine for threading bolt blanks which comprises a pair of forming dies for engaging opposite sides of bolt blanks and imparting a generally concave contour to the portions thereof which are to be threaded, one of said forming dies being stationary, means for reciprocating the other of said forming dies, a pair of thread-forming dies for engaging opposite sides of bolt blanks and causing threads to be rolled in them, one of said threading dies being stationary, means for reciprocating the other of said threading dies, means for feeding bolt blanks to said forming dies; and means for feeding th bolt blanks from said forming dies to aid threading dies, said forming and threading dies being arranged in tandem.

31. A machine for threading bolt blanks which comprises a pair of stationary dies, a pair of reciprocating dies, common means for reciprocating said reciprocating dies, one of said stationary dies and one of said reciprocating dies being forming dies cooperating'one with the other and shap d to impart a generally concaved contour to those portions of the bolt blanks which are to be threaded, the other of said stationary dies and the other of said reciprocating dies cooper.- ating one with the other and having threadforming faces for engaging opposite sides of bolt blanks,-means forfeeding bolt blanks to said forming dies and means for feeding bolt blanks from said forming dies to said threading dies.

32. A machine for threading bolt blanks Which comprises a pair of stationary dies, a pair of reciprocating dies, common means for reciprocat blanks to said forming dies and means for feeding bolt blanks from said forming dies to threading dies.

33. A machine for threading bolt blanks which comprises a pair of stationary dies, a pair of reciprocating dies, common mean for reciprocatsaid ing said reciprocating dies, one of said stationary dies and one of said reciprocating dies being forming dies cooperating one with the other and shaped to impart a generally concaved contour to those portions of the bolt blanks which are to be threaded, the other of said stationary dies and the other of said reciprocating dies cooperating one with the other and having thread-forming faces for engaging opposite sides of bolt blanks, the cooperating forming dies being located in a horizontal plane above the horizontal plane of the thread-forming dies, means for feeding bolt blanks to said forming dies, and means for causing bolt blanks from said forming dies to pass by gravity to the thread-forming dies.

34. A machine for threading bolt blanks which comprises a pair of relatively reciprocable roll ing dies adapted simultaneously to engage opposite sides of the shank of a bolt blank to be threaded and roll it preparatory to receiving a thread, a pair of relatively reciprocable threadrolling dies disposed in tandem with said first pair of dies, said thread rolling dies being posi tioned simultaneously to engage opposite sides of a rolled blank from said first pair of dies, and means for feeding shaped and formed blanks from said first pair of dies to said thread-rolling dies, including a starting pusher for engaging a rolled blank and initially pushing it to a position between the thread-rolling dies.

35. A machine forthreading bolt blanks which comprises a pair of relatively reciprocable platen rolling dies adapted simultaneously to engage opposite sides of the shank of a bolt blank to be threaded and roll it, a pair 01' threading platen rolling dies disposed in tandem with said first pair of dies, said threading dies being positioned simultaneously to engage opposite sides of a rolled .blank from said first pair of dies, means I for feeding rolled blanks from said first pair of dies to said threading dies, and means for reciprocating the threading dies relatively to develop a thread on a rolled blank disposed between them.

36. A machine for threading bolt blanks which comprises a pair of relatively reciprocable platen dies adapted simultaneously to engage opposite sides of a shank of a bolt blank to be threaded and shape it to size and form.to receive a thread, a pair of threading platen dies having coacting thread-producing surfaces thereon and disposed in, tandem with said first pair of dies, said threading dies being positioned simultaneously to en'- gage opposite sides of a shaped and formed blank from said first pair of dies, and means for feeding shaped and formed blanks from said first pair of dies to said second pair of dies, said feed ing means including a feed chute and a flapper bar operable independently of said dies.

37. A machine for threading bolt blanks which comprises a pair of stationary dies, a pair of reciprocating dies, common means for reciproeating said reciprocating dies, one of said stationary dies and one of said reciprocating dies being forming dies simultaneously engageable with opposite sides of the shank of a bolt blank to be threaded to shape it to size and form to receive a thread, the other of said stationary dies and the other of said reciprocating dies being threading dies simultaneously engageable with opposite sides of the shank of a shaped and formed blank to impart a thread thereto, and means for feeding shaped and formed bolt blanks from said forming dies to said threading dies.

38. A machine for threading bolt blanks which comprises a pair of stationary dies, apair of reciprocating dies, common means for reciprocating said reciprocating dies, one of said stationary dies and. one of said reciprocating dies being forming dies simultaneously engageable with opposite sides of the shank of a bolt blank to be threaded to shape it to size and form to receive a thread, the other of said stationary dies and the other of said reciprocating dies being threading dies simultaneously engageable with opposite sides of the shank of a shaped and formed blank to impart a thread thereto, and means for feeding shaped and formed bolt blanks from said forming dies to said threading dies, said feeding means including a flapper bar operable to feed bolt blanks from the forming dies of operation of the machine, means for feeding a blank to said form-rolling dies once during each cycle of operation of the machine, and means for feeding a blank shaped by said formrolling dies during a preceding operation to position between the thread-rolling dies once during each cycle of operation of the machine, whereby during each cycle of operation of the machine a blank is rolled to shape and a previously shaped blank has a thread rolled in it.

40. In a thread-rolling machine, two pairs of reciprocating-rolling dies, one of said pairs of dies having smooth working faces and the other having threading grooves formed on their working faces, driving means for affecting relative reciprocation of each of said pairs of dies once during each cycle of the machine, means for feeding a blank into position between said smoothfaced pair of dies once during each cycle of operation of the machine, and means for feeding into position between said other pairs of dies once during each cycle of operation of the machine, a blank rolled betwen said smooth-faced dies during a preceding cycle of operation of the machine.

41. In a thread-rolling machine, two pairs of relatively reciprocable rolling dies, driving means for afl'ecting relative reciprocation of each of said pairs of dies once during each cycle of operation of the machine, means for feeding a blank into position between one of said pairs of dies once during each cycle of operation of the machine, and separate means for transferring a.

blank from said one pair of dies into position between the other of said pairs of dies once during each cycle of operation of the machine.

42. In a thread-rolling machine, a supporting frame, a crank shaft journaled in said frame, two pairs of relatively reciprocable rolling dies, each of said pairs including a stationary die carried by said frame and a reciprocating die spaced from and movable parallel with its cooperating stationary die, driving means connecting each of said reciprocating dies with said crank shaft, means for feeding a blank to one said pairs of dies at the beginning of the relative reciprocatory movement of said one pair of dies from one dead center, and means for transferring a blank acted on by said one pair of dies and feeding the same to the other of said pairs of dies at the beginning of the relative reciprocatory movement of said other'palr of dies from, said one dead center.

43. In a thread-rolling machine, a frame, two pairs of relatively reciprocable platen rolling dies supported by said frame, the working faces of all of said dies being substantially parallel, each of said pairs of dies being adapted to engage the opposite sides of a blank and roll the same from a starting position to a discharge position, the discharge position of one of said pairs of dies being spaced transversely from the starting position of the other of said pairs of dies, and meansfor transferring blanks from the discharge position of said one pair of dies to the starting position of the other of said pairs of dies.

44. A machine for making threaded bolts comprising a pair of form-rolling dies arranged substantially horizontally and adapted simultaneously to engage opposite sides of the shank of a bolt blank, means for reciprocating the said dies relatively to shape the bolt blank preparatory to receiving a thread, a pair of thread-rolling dies disposed substantially horizontally at a different level than the forming dies and extending beyond them, said threading dies having coacting thread-producing surfaces thereon and I being positioned simultaneously to engage opposite sides of a shaped blank from the forming dies, means for feeding shaped blanks from the forming dies to the threading dies, and means for reciprbcating the threading dies relatively to develop a thread on a shaped blank disposed between them.

45. A machine for making threaded bolts comprising a pair of form-rolling dies arranged substantially horizontally and adapted simultaneously to engage opposite sides of the shank of a bolt blank, a pair of thread-rolling dies disposed substantially horizontally at a lower level than the forming dies and extending beyond them and having coacting thread-producing surfaces upon their adjacent faces, means for simultaneously reciprocating one of the forming dies and WILLIAM BAILEY. 

